Phosphate-containing and phosphonate-containing phosphate esters

ABSTRACT

There are disclosed multiphosphorus-containing compounds comprising phosphonate-containing or phosphate-containing phosphate esters. The compounds can be prepared by: (a) reacting a phosphonate-containing or phosphate-containing alcohol with phosphorus pentoxide following by reaction with an epoxide, (b) reacting a phosphonate-containing or phosphate-containing alcohol with a phosphorus oxyhalide, hydrolyzing any phosphorus halogen bonds and then reacting with the resulting phosphoric acid derivative with an epoxide, (c) transesterifying a phosphonate-containing or phosphate-containing alcohol with a dialkyl phosphite, oxidizing the resulting compound to yield a phosphoric acid derivative and reacting the phosphoric acid derivative with an epoxide. The compounds are useful as flame retardant additives for polyurethanes and textiles.

This is a continuation of application Ser. No. 423,838 filed Oct. 19,1989, now abandoned, which is a continuation of application Ser. No.306,113, filed Feb. 6, 1989, now U.S. Pat. No. 4,886,895, which is adivision of application Ser. No. 66,664, filed Jun. 26, 1987, now U.S.Pat. No. 4,820,854, which is a division of application Ser. No. 737,374,filed May 23, 1985, now U.S. Pat. No. 4,697,030.

FIELD OF THE INVENTION

The present invention relates to a novel class of phosphate-containingor phosphonate-containing phosphate esters. The present invention alsorelates to methods for the preparation of these compounds and the use ofthese compounds as flame retardant additives.

BACKGROUND OF THE INVENTION

In today's modern technology, phosphorus compounds play an increasinglyimportant role. These compounds find utility as flame retardantadditives for plastics and textiles, lubricant additives, biocides,herbicides, insecticides, pesticides, fungicides, growth regulators, oreflotation agents and metal plating additives.

Various classes of phosphorus derivative compounds are known.

U.S. Pat. No. 3,042,701 discloses phosphorus compounds having aplurality of pentavalent phosphorus ester radicals. The compoundsdisclosed in the above patent are selected from the class consisting ofphosphate diesters and phosphate-containing polyesters. The pentavalentstate is achieved by the oxidation or thionation of thephosphite-phosphonate intermediates to phosphate-phosphonates.

U.S. Pat. No. 2,372,244 discloses a process for the preparation of whatthe inventors believe to be "analogs of the alkylene glycol substitutedpartial esters of the acids of phosphorus".

U.S. Pat. No. 3,525,705 discloses a method for the production of fireresistant polyurethane products. In the method disclosed in the abovepatent, an organic polyisocyanate is reacted with the reaction productof the monoester of phosphoric acid, a mono or diester of diphosphoricacid, or a mono or diester of pyrophosphoric acid and an epoxide.

U.S. Pat. No. 2,909,559 discloses a process for producinghydroxyl-containing polymeric phosphate esters by heating ahydroxyl-containing phosphate ester of the structure: ##STR1## to atemperature of from about 90° C. to about 250° C.

SUMMARY OF THE INVENTION

The present invention is directed to organophosphorus compounds havingthe formula: ##STR2## wherein ##STR3## R₁, R₃ and R₅ are the same ordifferent and are alkyl, haloalkyl, aryl or haloaryl groups of from 1 toabout 20 carbon atoms, R₆ and R₇ are the same or different and arehydrogen, alkyl, haloalkyl, aryl or haloaryl groups of from 1 to about20 carbon atoms, R₂ and R₄ are the same or different and are alkylene orhaloalkylene of from 2 to about 10 carbon atoms, n is an integer from 1to 2, a can be 0 or 1, y is an integer from 1 to 10, and z is an integerfrom 1 to 10 with the proviso that n+a must equal 2.

The compounds of the present invention may be produced by a number ofprocesses.

In one embodiment of the present invention, a phosphate-containing orphosphonate-containing alcohol is reacted with phosphorus pentoxide,with or without an organic solvent. The resulting product is thenreacted with an epoxide to yield the desired product.

In another embodiment, a phosphate-containing or phosphonate-containingalcohol is reacted with a phosphorus oxyhalide in the presence of aLewis acid catalyst followed by hydrolysis of any remaining phosphorushalogen bonds to yield a phosphoric acid derivative. The phosphoric acidderivative is then reacted with an epoxide to yield the desired product.

In yet another embodiment of the present invention, aphosphate-containing or phosphonate-containing alcohol istransesterified with a dialkyl phosphite. In this reaction, thephosphate-containing or phosphonate-containing alcohol replaces one ortwo simple alkyl groups. The resulting phosphite is then oxidized to aphosphoric acid derivative by oxygen with, for example, nitrogendioxide. The resulting phosphoric acid derivative is then treated withan epoxide to yield the desired product.

Another embodiment of the present invention comprises the use of thenovel compounds of the present invention as flame-retardant additives.

In one embodiment, the novel compounds, in combination with a flexiblepolyurethane foam, produce a flame-retardant flexible foam compound.

In another embodiment, these compounds, in combination with a rigidpolyurethane foam, produce a rigid foam compound having improvedflame-retardant properties.

In yet another embodiment, the novel compounds of the present invention,when copolymerized with melamine derivatives, produce textile productshaving improved flame-retardant properties.

Other objects, features, and advantages of the present invention willbecome more apparent from the Detailed Description of the Inventionwhich follows.

DETAILED DESCRIPTION OF THE INVENTION

The novel compounds of the present invention are represented by theformula: ##STR4## R₁, R₃, and R₅ may be the same or different and arealkyl, haloalkyl, aryl, or haloaryl, R₆ and R₇ may be the same ordifferent and are hydrogen, alkyl, haloalkyl, aryl, or haloaryl, R₂ andR₄ may be the same or different and are alkylene and haloalkylene, n isan integer from 1 to 2, a can be 0 or 1, y is an integer from 1 to 10and z is an integer from 1 to 10. Preferably, the alkyl, haloalkyl,aryl, and haloaryl groups contain from 1 to about 20 carbon atoms, andthe alkylene and haloalkylene groups contain from 2 to about 10 carbonatoms.

The compounds of the present invention may be prepared by a variety ofmethods.

In one method, a phosphate-containing or phosphonate-containing alcohol,represented by the general formula ROH wherein R is as definedpreviously, is reacted with phosphorus pentoxide, with or without anorganic solvent. This reaction can be expressed as: ##STR5## whereincompound I is produced. Compound I is then reacted with an epoxide,represented by the general formula _(y) R₂ ═O wherein y and R₂ are aspreviously described, in a reaction which can be expressed as follows:Product II, thus obtained, may be referred to, when n is 1 or 2, as amultiphosphorus-containing phosphate ester.

In another embodiment, a phosphate-containing or phosphonate-containingalcohol, represented by the general formula ROH wherein R is as definedabove, is reacted with a phosphorus oxyhalide, represented by thegeneral formula POX₃ wherein X is a halogen, i.e., chlorine or bromine,in the presence of a Lewis acid catalyst in a reaction which can beexpressed as follows: ##STR6## Product III, a halogenated phosphate orphosphonate derivative, then undergoes hydrolysis of anyphosphorushalogen bonds in a reaction which can be expressed as follows:##STR7## Product IV, a multiphosphorus-containing ester is then reactedwith an epoxide represented by the formula _(y) R₂ ═O wherein y and R₂are as defined above in a reaction which yields Product II: ##STR8##

Suitable Lewis acid catalyst include magnesium chloride, stannicchloride, aluminum chloride, zinc chloride, and the like. The Lewis acidcatalyst is used in an amount ranging from about 0.1 percent to about 3percent by weight of the reaction mixture.

Suitable phosphorus oxyhalides include phosphorus oxychloride andphosphorus oxybromide.

The hydrolysis of any phosphorus-halide bond may be carried out by anymethod known to those skilled in the art.

Yet another process by which the compounds of the present invention canbe produced involves the transesterification of a phosphate-containingor phosphonate-containing alcohol, represented by the formula ROHwherein R is as defined above with a dialkyl phosphite represented bythe general formula ##STR9## wherein R₁ is as defined above, in thepresence of a catalyst, in a reaction which can be expressed as follows:##STR10## Product V, a phosphate-phosphite or phosphonate-phosphiteresults from the replacement of one or two simple alkyl groups by thephosphate-containing or phosphonate-containing alcohol.

Product V is then oxidized with oxygen and, for example, nitrogendioxide, in a reaction as follows: ##STR11## Product VI, a phosphoricacid derivative, is then reacted with an epoxide, represented by theformula _(y) R₂ ═O wherein y and R₂ are, as previously defined, to yieldthe compound of Formula II: ##STR12##

Suitable catalyst for the transesterification reaction of thephosphate-containing or phosphonate-containing alcohol and the dialkylphosphite include sodium methoxide, sodium ethoxide, and other alkoxidederivatives.

Suitable oxidants for the oxidation of the phosphate-phosphite orphosphonate-phosphite to the phosphoric acid include nitrogen dioxideand nitric oxide, or the oxidation can be done using oxygen in thepresence of a nitride catalyst.

When a phosphate-containing or phosphonate-containing alcohol is reactedwith phosphorus pentoxide, an amount ranging from about 1 to about 3moles of the phosphate-containing or phosphonate-containing alcohol permole of the phosphorus pentoxide, as P₂ O₅, may be used.

When a phosphate-containing or phosphonate-containing alcohol is reactedwith a phosphorus oxyhalide, an amount ranging from about 1 to about 3moles of the phosphate-containing or phosphonate-containing alcohol permole of the phosphorus oxyhalide may be used.

In a synthesis method wherein a phosphate-containing orphosphonate-containing alcohol is transesterified with a dialkylphosphite, an amount ranging from about 1 to about 2 moles of thephosphate-containing or phosphonate-containing alcohol per mole of thedialkyl phosphite may be used.

The phosphate-containing or phosphonate-containing alcohols of thepresent invention may be synthesized by a variety of methods with onemethod of synthesis of a phosphonate-containing alcohol being thereaction of a dialkyl phosphite, represented by ##STR13## with aformaldehyde derivative, such as paraformaldehyde, in the presence of acatalyst, such as triethylamine. One example is the reaction of diethylphosphite with paraformaldehyde in a 1:1 ratio in the presence oftriethylamine as a catalyst: ##STR14## Product VII, diethylhydroxymethylphosphonate (DEHMP), is a suitable phosphonate-containingalcohol which can be used in the processes of the present invention.

If a phosphate-containing alcohol is used, this type of alcohol may beprepared by reaction of a dialkyl hydrogen phosphate with an oxiranecompound. An example is the reaction of diethyl hydrogen phosphate withethylene oxide: ##STR15## Compound VIII, diethyl hydroxyethyl phosphate,is a suitable phosphate-containing alcohol which may be used in theprocesses of the present invention.

Halogenated phosphate-containing and/or halogenatedphosphonate-containing alcohols can also be used. Such alcohols may besynthesized by a number of reactions with one non-limiting example beingthe reaction of a tris(haloalkyl)phosphite with a hydrogen halide toproduce a bis(haloalkyl)phosphite in a reaction which may be expressedas follows: ##STR16## wherein R is an alkyl group of 1-20 carbon atomsand X is a halogen. The bis(haloalkyl)phosphite thus produced is thenreacted with an aldehyde, such as paraformaldehyde, in a reaction asfollows: ##STR17## wherein R and R' are alkyl groups of 1-20 carbonatoms, and X is a halogen.

Non-limiting examples of suitable phosphonate-containing alcohols whichmay be used in these syntheses are: ##STR18##

Non-limiting examples of suitable phosphate-containing alcohols whichmay be used in these syntheses are: ##STR19##

In addition to the above compounds, R₁, R₃, R₅, R₆ and R₇ can besuitable alkyl, haloalkyl, aryl and haloaryl groups such as, forexample, methyl, ethyl, propyl, 2 chloroethyl, 2,3-dibromopropyl, butyl,octyl, phenyl, tolyl and p-chlorophenyl.

In addition to the above compounds, R₆ and R₇ can be suitable alkyleneand haloalkylene groups derived from epoxides such as ethylene oxide,propylene oxide, butylene oxide, 4,4,4-trichlorobutylene oxide,epichlorohydrin, epibromohydrin and various glycidyl ethers.

Reaction of the phosphate-containing or phosphonate-containing alcoholwith phosphorus pentoxide takes place readily, generally, by suspendingthe phosphorus pentoxide in an appropriate suspending fluid, such astoluene, and then adding the phosphate-containing orphosphonate-containing alcohol in an inert atmosphere.

Reaction of the phosphate-containing or phosphonate-containing alcoholwith the phosphorus oxyhalide also takes place readily, generally, byslowly adding the phosphorus oxyhalide to a solution of thephosphate-containing or phosphonate-containing alcohol in the presenceof an appropriate catalyst, or catalysts. Generally, the reaction isexothermic and if the exotherm is cooled too rapidly, additional heatingmay be necessary. Hydrolysis of any of the remaining phosphorus halidebonds can be accomplished by any method known to those skilled in theart.

The transesterification of a phosphate-containing orphosphonate-containing alcohol with a dialkyl phosphite also takes placereadily, generally by mixing together the dialkyl phosphite and thephosphate-containing or phosphonate-containing alcohol in the presenceof an appropriate catalyst, such as sodium methoxide with controlledvaporization of the departing alcohol. The reaction usually requiressome heating. The oxidation is accomplished by gently bubbling in oxygenwith sodium nitride with controlling of the exotherm produced.

Generally, it is preferable that the temperature of the reactions of thepresent invention be kept between 50° C. and 90° C. Thus, depending onthe degree of exotherm seen, gradual cooling of the reaction mixture maybe necessary.

Reaction of any of the phosphoric acid derivatives produced by theimmediately aforementioned reactions with an oxirane, such as ethyleneor propylene oxide, also takes place readily, generally by bubbling theoxirane, if it is in gaseous form, or adding the oxirane dropwise, if itis in liquid form, to the phosphoric acid derivative. Gradual heating isused to bring the reaction to completion and the gaseous oxirane, ifsuch is used, can be stripped by any known technique such as sparging,etc.

It will be obvious to one skilled in the art that since the finalproduct represented by Formula II itself contains alcohol functions, itmay be reacted by any of the syntheses methods of the present inventionto yield higher homologs.

Similarly, the stoichiometry of the general reactions can be adjusted sothat the final phosphorus content, hydroxyl number and degree ofhydroxyl functionality meets one's desired specifications.

The compounds of the present invention may be used for any purpose forwhich phosphorus compounds are suitable, with some non-limiting proposedexamples of utility being:

1. As flame retardants for plastics such as polyurethanes, cellulosics,modified cellulosics, and polyesters.

2. As flame retardants for textiles such as cellulosics and polyesters.

3. As lubricant additives acting as a detergent, dispersive, corrosioninhibitor, and anti-erosion agents, anti-rust, extreme pressure additiveand viscosity index improver.

4. As metal extractors, ore flotation agents.

5. As surfactants and emulsifying agents.

6. As chelants and sequestering agents.

7. Metal plating additives.

One particular use for the compounds of the present invention is toprovide flame retardant properties to a number of combustible materials.An example is provided by the compound: ##STR20## produced by any of thereactions of the present invention. The above compound, whenincorporated into a flexible urethane foam formulation, imparts goodflame retardant properties to the flexible urethane foam.

Another example is provided by the compound: ##STR21## produced by anyof the processes of the present invention. This compound, when used in arigid foam formulation imparts flame retardant properties to the rigidurethane foam.

Another example is provided by the compound: ##STR22## produced by anyof the processes of the present invention. This compound, when usedcopolymerized with a trimethyl melamine derivative on 100% cottonflannel produced a fabric which exhibited flame retardant propertiesdurable through ten detergent washings.

The present invention can comprise, consist of, or consist essentiallyof the following non-limiting examples.

EXAMPLE I Preparation of Diethyl Hydroxymethylphosphonate

To a 2 liter, round bottomed flask fitted with a nitrogen inlet wereadded 500 grams (3.6 mole) of diethyl phosphite (Aldrich), 120 grams(3.8 mole) of paraformaldehyde (Baker) and approximately 6 millilitersof triethylamine. The mixture was stirred overnight at room temperaturebut no visible reaction had occurred so approximately 10 millilitersmore of triethylamine was added and the mixture was slowly warmed to 90°C. The solution was heated for approximately an additional hour,filtered hot and distilled. 320 grams of a liquid product correspondingto a 60% yield was obtained.

EXAMPLE 2 Preparation of Diethyl Hydrogen Phosphate

A dry 2 liter, 3-necked flask was equipped with a fritted gas bubbler,condenser, nitrogen inlet, thermometer and magnetic stirrer. The airline into the flask contained, in sequence, a drying tube (DRIERITE®+3A° sieve), a gas wash bottle containing 230 grams of nitrogen dioxideand a trap attached to the fritted gas bubbler. The flask was chargedwith 843 grams of diethyl phosphite, air was bubbled through thenitrogen dioxide and the nitrogen dioxide was, in turn, bubbled throughthe diethyl phosphite. After about 170 grams of nitrogen dioxide hadvaporized into the solution, the vapor phase turned reddish-brownindicating that the reaction was nearly complete so dry air was bubbledin. The the mixture was then placed on a rotary evaporator and strippedfor two hours at 60° C. at 5 millimeter Hg. The extracted compound hadthe following properties: 1.071 grams required 63.8 milliliters of 0.1Nbase to reach the methyl red end point, 1.071 grams of the compoundrequired 6.3 milliliters of 0.1N base to reach the phenolphthalein endpoint.

EXAMPLE 3 Preparation of Diethyl Phosphonophosphoric Acid

A 2 liter, 3-necked flamed out flask was equipped with a mechanicalstirrer, a dropping funnel, thermometer and reflux condenser. To thisflask were added 70 grams (0.49 mole) of phosphorus pentoxide (MCB) and380 grams reagent grade toluene (dried on a molecular sieve). Under anitrogen atmosphere, diethyl hydroxymethylphosphonate (DEHMP)synthesized by the procedure of Example 1 was added dropwise withstirring. After about 35 minutes, a total of 260 grams (1.55 moles) ofthe DEHMP had been added. The solution was heated at 90° C. for 3 hours.The solution was then cooled, and placed on a rotary evaporator for 13minutes. The final yield was 325 grams or 98% based on startingmaterials.

Titration with 0.1N base showed that 2.0 grams of the compound required63.2 milliliters to the methyl red end point and 23.7 milliliters to thephenolphthalein end point, corresponding to the compound having 3.2 megstrong acid/g (theoretical=3.1) and 1.2 meg weak acid/g(theoretical=1.5). Further analytical data showed a compound ofmolecular weight 310 corresponding to an average formula of: ##STR23##

EXAMPLE 4

A 500 milliliter 3-necked flask was charged with 143 grams (0.46 mole)of the diethyl phosphonophosphoric acid produced by the method ofExample 3 (previously titrated to methyl red end point showing an acidnumber of 177). The solution was warmed to 70° C. and 50 grams ofethylene oxide (Matheson) was gradually bubbled in. After the exothermceased, the solution was heated to 90° C. with refluxing of the ethyleneoxide for 45 minutes. The ethylene oxide was then stripped yielding118.1 grams of a water white oil. The molecular weight of the compoundwas 357 corresponding to an average formula of: ##STR24## The calculatedphosphorus percentage was 19%. The calculated OH number was 284. Fortitration, 2 grams of the compound were stirred into 0.1N HCl (10.0)milliliters. 17.9 milliliters of NaOH were required to the methyl redend point.

EXAMPLE 5

Similar to Example 4 except about 70 grams of propylene oxide was addeddropwise to the acid (acid number=177). 196.2 grams of a water whitematerial was obtained. Acid number=1.2 to a para-naphthol benzein (PNB)end point. The compound had an average formula: ##STR25## For titration2.0 grams were stirred into 10.0 milliliters of 0.1N HCl for 10 minutes.34.2 milliliters of 0.1N NaOH were required to the methyl red end point.HCl number=6.7

EXAMPLE 6 Synthesis of Diethyl Hydroxyethyl Phosphate

A 2 liter, 3-necked flask was equipped with a Dewar condenser, gas inletand stirring bar. 875 grams (5.7 mole) of diethyl hydrogen phosphate wasplaced into the flask and about 400 grams of ethylene oxide were addedover a 4 hour period. When the exotherm slowed, (pot temperature 50° C.)acid number=70. After the exotherm ceased and temperature dropped to 40°C., acid number=about 50. After refluxing of the ethylene oxide at 50°C. for 1 hour, acid number=about 18, after 3 hours at 50° C. acidnumber=about 7. All the above acid numbers were based on methyl red endpoint titration. The total yield was 1171 grams. Approximately half ofthe product was then wipe film distilled at 80° C. and 0.5 millimeterHg. NMR data showed a compound having the formula: ##STR26## acidnumber=1.7 to methyl red, 6.7 to PNB HCl acid to methyl red=14.3 tophenolphthalein=16.3

H₂ O acid number=4.8 to methyl red

HCl/H₂ O acid number=12.6 to methyl red

Thus, the compound had the structure ##STR27##

EXAMPLE 7

Into a 500 milliliter round bottom 3-necked flask was placed 32.7 grams(0.23 mole) of phosphorus pentoxide and 100 grams of toluene. 108 grams(0.69 mole) of diethyl hydroxyethyl phosphate produced according to themethod of Example 6 was added dropwise over a period of 3 minutes withvigorous stirring. The solution was warmed for 2 hours at 80° C.followed by stripping. There was obtained 140 grams of a compound of anaverage formula: ##STR28##

EXAMPLE 8

133 grams (0.435 mole) of the phosphatophosphoric acid obtained by theprocedure of Example 7 were placed into a 3-necked, round bottom flaskequipped with a Dewar condenser, gas inlet and magnetic stirrer. Thesolution was warmed to 50° C. and ethylene oxide was added at acontrolled rate so that the temperature remained at 50°-55° C. with someice cooling. After the exotherm ceased, excess ethylene oxide was added.The solution was stripped on a rotary evaporator at 10 millimeters Hgand 50° C. 182 grams of a light yellow viscous liquid was obtained.Titration results showed

    ______________________________________                                        acid number H.sub.2 O → methyl red                                                          1.7 mg KOH/g                                             toluene-isopropanol → PNB                                                                   1.4 mg KOH/g                                             ______________________________________                                    

The compound had an average approximate formula: ##STR29##

EXAMPLE 9

261 grams (1.23 mole) of diethyl hydroxyethylphosphate prepared by themethod of Example 6 was placed in a 1 liter round bottomed flask with150 milliliters of toluene and 58 grams (0.41 mole) of phosphoruspentoxide was added. The exotherm was controlled by the use of an icebath. When the exotherm ceased, the solution was heated for 1 hour at80° C. The heat was removed and 125 grams (2.8 moles) of ethylene oxidewas added with cooling till the exotherm ceased. The solution wasrefluxed for 1 hour at which point Acid number=about 2[(KOH:isopropanol:toluene)=2.7 milliliters 0.1N base for a 2.5 gramsample]. Ethylene oxide was then refluxed for 4 hours, at which pointAcid number=about 1 [(KOH:isopropanol:toluene) 0.4 milliliters of 0.1Nbase for 2.5 grams sample]. The solution was then placed on a rotaryevaporator at 60° C. at 10 millimeters Hg. There was obtained 400 gramsof a compound having the formula: ##STR30## The calculated molecularweight was 487. Calculated % P was 15.9, calculated OH number=173, KOHacid number=0.8 mg KOH/g.

EXAMPLE 10

To a 1 liter, 3-necked round bottomed flask equipped with a thermometer,nitrogen inlet, mechanical stirrer and dropping funnel was added 44.7grams (0.31 mole) of phosphorus pentoxide dissolved in 50 milliliters oftoluene. To the flask was then added slowly 168 grams (0.31 mole) ofDEHMP in 100 milliliters of toluene. The mixture was heated to 70° C. to80° C. for 2 hours and then allowed to cool to room temperature. Thesolution was stripped on a rotary evaporator at 10 mm Hg at 90° C. 2.0grams of the intermediate required 58.5 milliliters of 0.1N NaOH tomethyl red end point and 10.5 milliliters to phenolphthalein end point.

To 192 grams (0.5 mole) of the above intermediate was added 90 grams (2mole) of ethylene oxide. After all the ethylene oxide had been added,the solution was stripped on a rotary evaporator at 15 mm Hg at 50° C.Analytical results showed:

    ______________________________________                                                   % P =  19.4                                                                   OH # = 160                                                                    Acid # =                                                                             4.6                                                         ______________________________________                                    

The compound had the average formula: ##STR31##

Examples 11-13 illustrate the synthesis of a halogenatedphosphate-containing or phosphonate-containing phosphate ester of thepresent invention.

EXAMPLE 11 Preparation of Bis(Betachloroethyl)Phosphite

Into a 1 liter 3-necked flask equipped with a reflux condenser,mechanical stirrer, thermometer, and nitrogen inlet was added 500 grams(1.85 mole) of tris(betachloroethyl)phosphite and 75 grams (0.91 mole)of phosphorous acid. The mixture was heated to 80°-90° C. for about 1.5hours. The ASTM acid # of the compound was 2.0.

EXAMPLE 12 Preparation of Bis(Betachloroethyl)Hydroxymethylphosphate

By reacting 375 grams (1.81 mole) of the bis(betachloroethyl)phosphiteof Example 11 with 60 grams (1.9 mole) of paraformaldehyde in thepresence of 30 grams of triethylamine, thebis(betachloroethyl)hydroxymethylphosphonate compound was produced.

EXAMPLE 13

To a 1 liter, 3-necked round bottomed flask equipped with a refluxcondenser, thermometer and magnetic stirrer was added 91 grams (0.384mole) of the bis(betachloroethyl)-hydroxymethylphosphonate of Example12, 100 grams of toluene and 18.2 grams (0.128 mole) of phosphoruspentoxide. The solution was heated at reflux for 1 hour and then cooledto 25° C. 30 grams of propylene oxide was added, the exotherm wasallowed to cease, and an additional 20 grams of propylene oxide wasadded. The solvent was removed and the remaining solution was wipe filmdistilled at 1 mm Hg. The final ASTM acid # was 0.3. The compound hadthe average formula: ##STR32##

EXAMPLE 14

This example illustrates the reaction of a phosphorus oxyhalide with aphosphate-containing or phosphonate-containing alcohol.

To a 1 liter, 3-necked, round bottom flask equipped with a mechanicalstirrer, thermometer, H₂ O condenser, a nitrogen inlet over the outletof condenser to drying tube and an addition funnel were added 200milliliters of 1,2-dichloroethane, 168 grams (1.2 mole) of diethylhydroxymethylphosphonate synthesized by the procedure of Example 1, 105grams of triethylamine and 2 grams of magnesium chloride. 4.9 grams(0.35 mole) of phosphorus oxychloride was added to the addition funnel.The 3-necked flask was heated to 80° C. and the addition of thephosphorus oxychloride was started. The exotherm was cooled in a waterbath and the solution was heated again. After complete addition of thephosphorus oxychloride (15-20 minutes) infrared spectra showed a strongOH peak so the solution was heated an additional 3 hours. Attermination, 400 cc of 1,2-dichloroethane was added, the mixture waswashed once with 500 cc of 1N HCl, then twice with 500 cc H₂ O followedby 500 cc of 0.5N NaOH and finally twice with 500 cc H₂ O. The solutionwas dried over MgSO₄ and then placed on a rotary evaporator at 50° C. at10 millimeters Hg. Acid number=<0.1 mg KOH/g. The compound had anaverage formula: ##STR33## and wastris(diethylmethylphosphonate)phosphate.

EXAMPLE 15

315 grams (1.9 mole) of diethylhydroxymethylphosphate (acid number=0.3)prepared by the process of Example 1, 300 grams (2.2 moles) of diethylphosphite (Stauffer), and 2 grams (25%) in methanol of sodium methoxidewere added to a 2 liter round bottom flask which was equipped with athermometer and Vigreaux column leading to a dry ice trap and Drierite®trap and aspirator. The solution was warmed to 40° C. for 1 hour at 20millimeters Hg. Volatiles collected in the dry ice trap. After 115milliliters of volatiles had been collected, the solution was placed ona rotary evaporator. The compound produced is then placed in a 250milliliter 3-necked, round bottom flask and oxygen and nitric oxide arebubbled in simultaneously. Alternatively, the oxygen and nitric oxidecan be mixed in the Y tube and then bubbled into the mixture.

EXAMPLE 16

The composition produced according to Example 9, ##STR34## wasincorporated at 12 p.h.r. into a flexible polyurethane foam having thefollowing formulation:

    ______________________________________                                                       Parts by Weight                                                ______________________________________                                        Polyol           1.0                                                          Silicone surfactant                                                                            1.0                                                          Water            4.0                                                          Amine catalysts  0.50                                                         Stannous octoate 0.25                                                         Toluene diisocyanate                                                                           55.1                                                         ______________________________________                                    

The foam mixture was poured into an open-top box and allowed to expandinto a 15 inch square block. It was then oven cured at 130° C. for about10 minutes. This was followed by ambient temperature curing for 3 days.

Flammability testing was conducted pursuant to the Motor Vehicle SafetyStandard 302 (MVSS-302). A control foam of the same formulation withoutthe flame retardant was also prepared and tested for flammability.

In the MVSS-302 test, a specimen of foam 4 inches×1/2 inch thick by 14inches long is held horizontally between 2 V-shaped brackets whichallows free access of air above and below. The specimen is ignited by abunsen burner and the burning rate in inches per minute is measured. Aburn rate below 4 inches/minute is usually required.

General Motors Corporation uses the following qualitative measures underMVSS-302.

    ______________________________________                                        Does not ignite      DNI                                                      Self-extinguishes (SE) before first                                                                SE                                                       mark (before 11/2 inch total)                                                 SE in less than 31/2 inches total                                                                  SE/NBR                                                   SE after 31/2 inches from starting                                                                 SE, alpha burn rate                                      point                                                                         Burns full length    burn rate                                                ______________________________________                                        The flammability results were as follows:                                     MVSS-302   Control   FLAME RETARDED FOAM                                      ______________________________________                                        Initial Rating                                                                           Burn      SE                                                       Avg. inch burned                                                                          11.50    --                                                       Avg. sec. burned                                                                         130.00    --                                                       Burn rate   4.63     --                                                       DHA # rating                                                                             Burn      SE                                                       Avg. inch burned                                                                          9.90     --                                                       Avg. sec. burned                                                                         107.89    --                                                       Burn rate   4.92     --                                                       ______________________________________                                         *Dry heat average for 22 hours at 140° C.                         

Since the samples self-extinguished after the first flame application,the samples were given a SE rating.

EXAMPLE 17

By changing the formulation of the foam produced by following theprocedure of Example 16, a rigid polyurethane foam can be produced. Alsoby following the procedure of Example 16, a compound of the presentinvention can be incorporated as a flame retardant additive into a rigidpolyurethane foam.

EXAMPLE 18

The hydroxyethoxyphosphonophosphate produced by the procedure of Example10 was tested as a flame retardant for textiles. The padding bath forthe textiles tested was prepared according to the procedure set forth inU.S. Pat. No. 3,746,572, the subject matter therein being incorporatedby reference. The treated textiles were tested for flammabilityresistance by the Department of Commerce (DOC) FF3-71 flammability test.Particulars of this test are available from the Department of Commerce.The samples were tested after hot washes (HW) and after 5 detergentwashes (DW). The number of inches burned was measured with burned entirelength (BEL) being an unacceptable flame retardant for the particulartextile. As can be seen from TABLE I, the compound produced excellentresults as a flame retardant for 100 percent cotton flannel.

                  TABLE I                                                         ______________________________________                                                      %                                                               Experiment #  Solid  1       2     3     4                                    ______________________________________                                        Water         --     39.1    18.9  59.4  45.9                                 Surfactant (Triton                                                                          10     0.1     0.1   0.1   0.1                                  X100)                                                                         Hydroxyethoxy Phos-                                                                         100    31.5    31.5  21    21                                   phonophosphate.sup.1                                                          Aminoplast (Aerotex                                                                         80     76.3          17.5                                       M3)                                                                           Zinc nitrate Catalyst                                                                       25     3             2                                          (X4)                                                                          NMA           60             34.5        23                                   Potassium Dithionate                                                                         5             15          10                                   Fabric:          50% polyester/                                                                            100% cotton                                                       50% cotton                                                   Dry conditions °F./min.                                                                 250/3       250/2                                            Cure conditions °F./min.                                                                350/3       350/2                                            Weight before padding                                                                          23.0    23.0    15.7  16.3                                   (bond dry - 5 min.)                                                           Weight after padding                                                                           42.6    42.3    34.2  34.5                                   % Wet pick-up    85.2    84.0    118   111                                    Weight after cure                                                                              31.8    31.9    21.0  21.4                                   (before HW)                                                                   % Add-on (before HW)                                                                           38.2    38.4    34.0  30.9                                   Theoretical % add-on                                                                           44.7    43.8    41.3  38.9                                   (before HW)                                                                   Weight after 1 HW                                                                              29.9    29.2    20.5  20.5                                   (bone dry - 10 min.)                                                          % Add-on (after HW)                                                                            30.0    26.9    30.7  25.5                                   % Retention after HW                                                                           78.5    70.1    90.3  82.5                                   % Add-on (after 10 DW)                                                                         21.3            21.0  10.7                                   % Retention after 10DW                                                                         71.0            68.4  42.0                                   Overall retention                                                                              55.8            61.8  34.6                                   Hand:                                                                         Before HW        5       4.5     5     4                                      After HW         5       4       4     3                                      After 10 DW      3               3     2.5                                    Color:                                                                        Before HW        off     yellow  off   lt.                                                     white           white yellow                                 After HW         off     yellow  off   lt.                                                     white           white yellow                                 After 10 DW      off             off   lt.                                                     white           white yellow                                 Flame test FF3-71                                                             Before HW                                                                     After HW         4.5     BEL     2.75  4.0                                    After 10 DW      BEL             4.5   BEL                                    ______________________________________                                         ##STR35##                                                                

Additional features of the preferred and most preferred embodiments ofthe present invention are found in the claims hereinafter.

What is claimed is:
 1. A compound of the formula: ##STR36## wherein Ris: ##STR37## or R is ##STR38## R₃ and R₅ are the same of different andare alkyl, haloalkyl, aryl, or haloaryl;R₄ is alkylene or haloalkylene;R₆ and R₇ are the same or different and are hydrogen, alkyl, haloalkyl,aryl or haloaryl; n is an integer from 1-2; z is an integer from 1-10.2. The compound of claim 1 wherein R₃ or R₅ is C₁ -C₂₀ alkyl, haloalkyl,aryl or haloaryl.
 3. The compound of claim 1 wherein R₆ and R₇ are C₁-C₂₀ alkyl, haloalkyl, aryl or haloaryl.
 4. The compound of claim 1wherein R₆ or R₇ is hydrogen.
 5. The compound of claim 1 wherein R₃ orR₅ is ethyl.
 6. The compound of claim 1 wherein R₆ or R₇ is ethyl. 7.The compound of claim 1 wherein R₄ is ethylene.
 8. The compound of claim1 wherein R₃ or R₅ is methyl.
 9. The compound of claim 1 wherein R₆ orR₇ is methyl.